Hello

Recently i have a problem with a joomla 2.5 and k2 2.5.4 sometimes when i try to upload a single photo in an item i get a blank screen, i have to reload the page and thats it... no image uploaded of course.
Checking the log i saw this:

PHP Notice: Undefined property: stdClass::$imagenone in /path-to-joomla/components/com_k2/helpers/utilities.php on line 185

i have that error a lot... maybe thats whats causing this, any idea on how to fix it? thank you.